A new type of capillary column for open-tubular electrochromatography

• Published in: Electrophoresis Vol. 23; no. 17; pp. 2990 - 2995
• Main Authors: Zhao, Yingxin, Zhao, Rui, Shangguan, Dihua, Liu, Guoquan
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 01.09.2002; WILEY‐VCH Verlag
• Subjects: Chromatography - instrumentation; Chromatography - methods; Electrophoresis, Capillary - instrumentation; Electrophoresis, Capillary - methods; Indicators and Reagents; Open-tubular capillary electrochromatography; Peptides; Reproducibility of Results; Silanes - chemical synthesis; Silanes - chemistry; Sol-gel technology
• DOI: 10.1002/1522-2683(200209)23:17<2990::AID-ELPS2990>3.0.CO;2-7
• ISSN: 0173-0835

A new type of open‐tubular C18 ester‐bonded electrochromatographic column was prepared with sol‐gel technology, followed by an on‐column octadecyl silylation reaction. Glycidoxypropyltrimethoxysilane, a widely used and important silane agent, was used as the sol‐gel precursor to form a thin coating layer on the wall of the fused‐silica capillary. The C18 groups were introduced into the coating layer by on‐column esterification reaction with stearic acid. The electrochromatography behavior of the column was evaluated in terms of the separation of peptides. A high efficiency of 4.8×105 plates/m was achieved for a basic pentapeptide using the C18 ester‐bonded column. In comparison with bare capillaries and glycidoxypropyltrimethoxysilane sol‐gel‐coated capillaries, the C18 ester‐bonded column showed the best separation of a mixture of seven pentapeptides under identical conditions of buffer, pH, and applied voltage.